The present disclosure is directed generally toward capacitance based clearance probes, and more specifically toward a capacitance based clearance probe built into a metal surface.
Gas turbine engines, such as those utilized in commercial aircraft, include multiple rotors and stators configured to enable optimal operation. Turbine engines maintain an optimal clearance (distance) between the tips of the rotors and an outside diameter of a gas path within the turbine engine, and thereby provide the conditions necessary to achieve a desired performance.
The gas turbine engine performance is validated, in part, by measuring the blade tip clearance. In order to measure the tip clearance, one or more tip clearance probes are installed in the outer air seal wall of the turbine engine. As the tip clearance probes are incorporated onto the outer air seal of the gas turbine after the outer air seal has been manufactured, it is necessary to re-operate the outer air seal casing to accommodate the tip clearance probe. Existing tip clearance probe arrangements require the outer air seal casing to further accommodate the housing of the tip clearance probe, thereby limiting the locations on the outer air seal that can accept the tip clearance probe and requiring significant additional re-operation of the outer air seal.